I've been looking into tires for my MTB tourer for an off-road tour and am leaning towards the Schwalbe Marathon XR's for their puncture resistance and good reputation. Should I go for the 1.9" tires or a wider tire, such as a 2.2" for more "cushion" for my rigid MTB? Opinions?

I'm hoping to do the whole Great Divide route if I can get started before September, or I'm kinda' looking at a Tibet trip that looks interesting... I don't really care about putting too much pressure in my tires since I've been pretty happy around town at about 40 lbs on my previous bike. I'm sure I'll go a little higher when fully loaded but like to have some shock absorption down there as opposed to my hands & wrists, which is why I was considering a wider tire. I'll have to check on clearance issues but I might just go with the 1.9" since they have pretty good deals on them at Performance & Wall Bike (last year's model Marathon XR).

I toured a few weeks ago a pair of WTB Terrainasaurus 1.95. I had bought them last fall to use on my "daily driver" . I put them on the touring bike because this spring has been very wet and many of the rail trails, abandoned railbeds and towpaths I like to ride have been soft and muddy at times. The size worked well for me It was certainly less effort to ride on the trails with a 1.95 tire as opposed to a 1.5. I didn't notice this particular 1.95 tire being much slower on the road than the 1.5 IRC's I usually use. I may leave the WTB's on for my 1000 Islands tour this year to see how they do on a long road tour

I have used 2.2 panaracer knobbies on my MTB. The hassle with that size on my bike has always been the tires won't easily get past the brake shoes when inflated. I always have to let some air out and squeeze the tire to get past the shoes.